MYSQLAlchemy/Flask doesn't recognise migrations - python

I am new to Flask/MYSQLAlchemy/Postgres and am still trying to understand it all.
I have got an app:
from flask import Flask
from flask_cors import CORS
import sentry_sdk
from sentry_sdk.integrations.flask import FlaskIntegration
def create_app(*args, app_name="SMARRTBROKER_API"):
# add sentry integration
sentry_sdk.init(
dsn="https://cd31f9dbcd56420fa0ca08422a441747#sentry.io/1369455",
integrations=[FlaskIntegration()]
)
app = Flask(app_name)
CORS(app, resources=r'/api/*')
# CORS(app, resources={r"/api/*": {"origins": "*"}}, supports_credentials=True)
app.config.from_object('api.config.DevelopmentConfig')
from api.api import api
app.register_blueprint(api, url_prefix='/api')
# app.config['SQLALCHEMY_ECHO'] = True
from api.models import db
db.init_app(app)
return app
And a manage.py file:
from flask_script import Manager
from flask_migrate import Migrate, MigrateCommand
from api.application import create_app
from api.models import db, Lead, User, Setting, Category, Keyword, keyword_identifier, Product, Plan
from filter_class import Filter
from filter_keyword import FilterKeyword
from sqlalchemy.dialects.postgresql import array
from sqlalchemy import or_, not_
from sqlalchemy import any_
from datetime import datetime, timedelta
from sqlalchemy.orm.attributes import flag_modified
from classification import Classification
app = create_app()
migrate = Migrate(app, db)
manager = Manager(app)
# provide a migration utility command
manager.add_command('db', MigrateCommand)
if __name__ == '__main__':
manager.run()
And a model.py file:
"""
models.py
Data classes for the api application
"""
from datetime import datetime
from flask_sqlalchemy import SQLAlchemy
from werkzeug.security import generate_password_hash, check_password_hash
from sqlalchemy.ext.mutable import Mutable
from sqlalchemy.dialects.postgresql import ARRAY
import enum
import locale
db = SQLAlchemy()
...
class Setting(db.Model):
__tablename__ = 'settings'
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.Text, nullable=False)
created_at = db.Column(db.DateTime, default=datetime.utcnow)
updated_at = db.Column(db.DateTime, default=datetime.utcnow)
import_settings = db.Column(db.JSON, nullable=True)
def to_dict(self):
return dict(
id=self.id,
name=self.name,
created_at=self.created_at,
label=self.label
)
class Keyword(db.Model):
__tablename__ = 'keywords'
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.Text, nullable=False)
label = db.Column(db.Text, nullable=False, unique=True)
created_at = db.Column(db.DateTime, default=datetime.utcnow)
updated_at = db.Column(db.DateTime, default=datetime.utcnow)
leads = db.relationship('Lead', secondary=keyword_identifier)
def to_dict(self):
return dict(
id=self.id,
label=self.label,
name=self.name,
created_at=self.created_at
)
...
And up until a couple weeks ago, if I made any change in the models file, I could run python manage.py db migrate and python manage.py db upgrade and the models were amended and the migration would take place without problems. Now, for whatever reason, when I run the migrate/upgrade commands, nothing happens and it seems that my changes were not recognised at all. Any ideas of why?

Related

Flask migration is not applying on all tables

i have a project where i create four tables (users,products, agents, customer) when i do migration with:
flask db init,
flask db migrate,
flask db upgrade,
only users and products get migrated
here it is the structure of my project:
my code for user model is:
from main.extensions import db
from main.shared.base_model import BaseModel, HasCreatedAt,
HasUpdatedAt
class User(BaseModel, HasCreatedAt, HasUpdatedAt):
tablename = 'users'
id = db.Column(db.Integer, primary_key=True)
email = db.Column(db.String, unique=True, nullable=False)
password = db.Column(db.String, nullable=False)
phone = db.Column(db.Integer)
my code for every module starting by agent model:
from main.extensions import db
class Agent(db.Model):
__tablename__ = 'agents'
id = db.Column(db.Integer, primary_key=True)
picture = db.Column(db.String)
def __init__(self,email, password, phone, picture):
self.email = email
self.password=password
self.phone=phone
self.picture=picture
and for the model in customer is:
from main.modules.user.models import User
from main.extensions import db
class Customer(User):
__tablename__ = 'customers'
approved = db.Column(db.Boolean)
picture = db.Column(db.String)
def __init__(self, email, password, phone, picture, approved):
self.approved = approved
self.picture = picture
User.__init__(self,email,password,phone)
and finnaly the products model has:
from main.extensions import db
from main.shared.base_model import BaseModel, HasCreatedAt, HasUpdatedAt
class Product(BaseModel, HasCreatedAt, HasUpdatedAt):
__tablename__ = 'products'
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.String, nullable=False)
the settings.py contains the following code:
and this init files for every model contains this code:
for the user __init.py:
from main.modules.users.api import blueprint as api
for the customer __init.py:
from main.modules.customer.api import blueprint as api
for the agent__init.py:
from main.modules.agent.api import blueprint as api
for the prodcut__init.py:
from main.modules.product.api import blueprint as api
import os
class DevSettings(Settings):
DEBUG = True
basedir = os.path.abspath(os.path.dirname(__file__))
SQLALCHEMY_DATABASE_URI="sqlite:///" + os.path.join(basedir, "data.sqlite")
SQLALCHEMY_TRACK_MODIFICATIONS=False
and the extension.py contains:
from flask_migrate import Migrate
from flask_sqlalchemy import SQLAlchemy
db = SQLAlchemy()
migrate = Migrate()
and the app.py contains this:
from flask import Flask, Blueprint
from main.extensions import db, migrate
from main.modules import product, agent, customer, user
from main.settings import DevSettings
MODULES = [ agent, customer,product, user]
main = Blueprint('main', __name__)
def create_app(settings=DevSettings):
app = Flask(__name__)
# Utiliser la configuration (settings).
app.config.from_object(settings)
app.config['SECRET_KEY'] = 'mysecretkey'
# On initialise les libraries Python.
# Init SQLAlchemy.
db.init_app(app)
# Init Migrate.
migrate.init_app(app, db)
app.register_blueprint(main)
register_modules(app)
return app
def register_modules(app):
for m in MODULES:
if hasattr(m, 'api'):
app.register_blueprint(m.api)

How to retrieve a row from SQLalchemy with flask

I am learning how to use SQLalchemy and databases in general with flask. I am following a tutorial and it uses the below classes and files.
https://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-iv-database
To show an inserted row in the database, the tutorial uses the following:
from app.models import User
>>> u = User(username='susan', email='susan#example.com')
>>> u
<User susan>
My problem is that I can not display the same output. I mean when I code the the statement, I get an error
from app.models import User
ImportError: No module named app.models
Please let me know how to adapt the posted code so I can retrieve data from database
Folder Structure:
d:\xxx\xxx\db1\app\models
d:\xxx\xxx\db1\__init__
d:\xxx\xxx\db1\config
** init **:
from flask import Flask
from config import Config
from flask_sqlalchemy import SQLAlchemy
from flask_migrate import Migrate
app = Flask(__name__)
app.config.from_object(Config)
db = SQLAlchemy(app)
migrate = Migrate(app, db)
from app import routes, models
config:
import os
basedir = os.path.abspath(os.path.dirname(__file__))
class Config(object):
# ...
SQLALCHEMY_DATABASE_URI = os.environ.get('DATABASE_URL') or \
'sqlite:///' + os.path.join(basedir, 'app.db')
SQLALCHEMY_TRACK_MODIFICATIONS = False
models:
from app import db
from app.models import User
class User(db.Model):
id = db.Column(db.Integer, primaty_key=True)
username = db.Column(db.String(64), index=True, unique=True)
email = db.Column(db.String(120), index=True, unique=True)
password_hash = db.Column(db.String(128))
def __repr__(self):
return '<User {}>'.format(self.username)
You cannot import User on the same module where models is declared, so I don't think If you need that second line in models.py, Try commenting and see what happens
from app import db
from app.models import User ## I think the problems is
class User(db.Model):
id = db.Column(db.Integer, primaty_key=True)
username = db.Column(db.String(64), index=True, unique=True)
email = db.Column(db.String(120), index=True, unique=True)
password_hash = db.Column(db.String(128))
def __repr__(self):
return '<User {}>'.format(self.username)

Flask-marshmallow ImportError: cannot import name fields

I started learning flask a few weeks ago and I followed flask mega tutorial. Now I want to do some programming myself and I tried to return data from database in json format using flask-marshmallow and I got stuck. I got an error saying ImportError: cannot import name fields.
This is full error message
This is models.py module:
followers = db.Table('followers',
db.Column('follower_id', db.Integer, db.ForeignKey('user.id')),
db.Column('followed_id', db.Integer, db.ForeignKey('user.id')))
class User(UserMixin, db.Model):
id = db.Column(db.Integer, primary_key=True)
username = db.Column(db.String(64), index=True, unique=True)
email = db.Column(db.String(120), index=True, unique=True)
country = db.Column(db.String(140))
nationality = db.Column(db.String(140))
password_hash = db.Column(db.String(128))
# Definisanje veze sa Post tabelom
posts = db.relationship('Post', backref='author', lazy='dynamic')
about_me = db.Column(db.String(140))
last_seen = db.Column(db.DateTime, default=datetime.utcnow())
# Definisanje veze sa followers tabelom
followed = db.relationship(
'User', secondary=followers,
primaryjoin=(followers.c.follower_id == id),
secondaryjoin=(followers.c.followed_id == id),
backref=db.backref('followers', lazy='dynamic'), lazy='dynamic')
class Post(db.Model):
id = db.Column(db.Integer, primary_key=True)
body = db.Column(db.String(140))
timestamp = db.Column(db.DateTime, index=True, default=datetime.utcnow)
user_id = db.Column(db.Integer, db.ForeignKey('user.id'))
def __repr__(self):
return '<Post {}>'.format(self.body)
#Declaring marshmallow ModelSchema
class UserSchema(ma.ModelSchema):
class Meta:
model = User
This is routes.py module:
#app.route('/all_users', methods=['GET'])
def get_all_users():
users = User.query.all()
user_schema = UserSchema(many=True)
out = user_schema.dump(users).data
return jsonify(out)
I didn't include all code but I will provide it if it's necessary.
Since error message point me to microblog.py and init.py, also modules in my app, so I will include these two modules.
microblog.py
from app import app, db
from app.models import User, Post
#app.shell_context_processor
def make_shell_context():
return {'db': db, 'User': User, 'Post': Post}
__init__.py
from flask import Flask
from logging.handlers import RotatingFileHandler
import logging
from config import Config
from flask_sqlalchemy import SQLAlchemy
from flask_marshmallow import Marshmallow
from flask_migrate import Migrate
from flask_login import LoginManager
from flask_mail import Mail
from flask_bootstrap import Bootstrap
from flask_moment import Moment
import os
'''Inicijalizacija ekstenzija'''
app = Flask(__name__)
app.config.from_object(Config)
db = SQLAlchemy(app)
migrate = Migrate(app, db)
login = LoginManager(app)
login.login_view = 'login'
mail = Mail(app)
bootstrap = Bootstrap(app)
moment = Moment(app)
ma = Marshmallow(app)
from app import routes, models, errors
if not app.debug:
if not os.path.exists('logs'):
os.mkdir('logs')
file_handler = RotatingFileHandler('logs/microblog.log', maxBytes=10240,
backupCount=10)
file_handler.setFormatter(logging.Formatter(
'%(asctime)s %(levelname)s: %(message)s [in %(pathname)s:%(lineno)d]'))
file_handler.setLevel(logging.INFO)
app.logger.addHandler(file_handler)
app.logger.setLevel(logging.INFO)
app.logger.info('Microblog startup')

SQLAlchemy don't create tables if using Marshmallow

I'm trying to create a project using Flask, Flask-SQLAlchemy, flask-restplus and marshmallow (tried with flask-marshmallow too), but the integration of these tools does not work very well.
Everytime I include some new lib, a new error occur.
I already give up to use migrations with Flask-SQLAlchemy because for some reason, this thing don't work. But now, the problem is with marshmallow.
I'm trying to make with modules and I think this is the part of the problem (all examples of Flask-SQLAlchmey, flask-restplus, flask-marshmallow, etc put everything in a single file)
This is my app.py:
from flask import Flask, Blueprint
import settings
from api import api
from database import init_database, reset_database
app = Flask(__name__)
def configure_app(flask_app):
flask_app.config['SERVER_NAME'] = settings.SERVER_ADDRESS
flask_app.secret_key = settings.SECRET_KEY
def initialize_app(flask_app):
configure_app(flask_app)
blueprint = Blueprint('api', __name__, url_prefix=settings.URL_PREFIX)
api.init_app(blueprint)
# api.add_namespace(auth_login_namespace)
flask_app.register_blueprint(blueprint)
init_database(flask_app)
if settings.DEBUG:
reset_database(flask_app)
def main():
initialize_app(app)
app.run(debug=settings.DEBUG)
if __name__ == '__main__':
main()
api/__init__.py:
import settings
from flask_restplus import Api
api = Api(
version='1.0',
title='Test',
description='Some description'
)
#api.errorhandler
def default_error_handler(e):
message = 'An unhandled exception occurred.'
if not settings.DEBUG:
return {'message': message}, 500
database/__init__.py:
from flask_sqlalchemy import SQLAlchemy
import settings
db = SQLAlchemy()
def init_database(flask_app):
flask_app.config['SQLALCHEMY_DATABASE_URI'] = settings.DATABASE_URI
flask_app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
global db # I really don't like this! :(
db = SQLAlchemy(flask_app)
def reset_database(flask_app):
from database.models import User
db.drop_all()
db.create_all()
db.session.add(User(username='admin', email='abc#def.com', name='admin', password='123', admin=True)
db.session.commit()
I have my app, with only one model until now:
database/models/User.py:
from marshmallow import Schema, fields
from sqlalchemy import func
from database import db
class User(db.Model):
id = db.Column(db.Integer, primary_key=True)
username = db.Column(db.String(80), unique=True, index=True)
email = db.Column(db.String(120), unique=True, index=True)
name = db.Column(db.String(200), nullable=False)
password = db.Column(db.String(200), nullable=False)
admin = db.Column(db.Boolean, nullable=False, default=False)
created_on = db.Column(db.DateTime, nullable=False, server_default=func.now())
class UserSchema(Schema):
id = fields.Int(dump_only=True)
username = fields.Str()
email = fields.Email()
name = fields.Str()
password = fields.Str()
admin = fields.Bool()
created_on = fields.DateTime()
now, if I use the following code (this code is called everytime my app start on debug mode, on function reset_database, in file database/__init__.py):
db.drop_all()
db.create_all()
db.session.add(User(username='admin', email='abc#def.com', name='admin', password='123', admin=True)
db.session.commit()
the User table is not created, and the admin is not inserted on table, because the table don't exist (db.create_all() don't create anything).
sqlite3.OperationalError: no such table: user.
For some reason, if I remove the class UserSchema (on database/models/User.py), the db.create_all() function create the table).
Got working right now:
on database/__init__.py, altered the init_database function to:
def init_database(flask_app):
flask_app.config['SQLALCHEMY_DATABASE_URI'] = settings.DATABASE_URI
flask_app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
db.init_app(flask_app)
and in database/reset_database.py:
def reset_database(flask_app):
with flask_app.app_context():
from database.models.user_module import User
db.drop_all()
db.create_all()
db.session.add(User(username='admin', email='abc#def.com', name='admin', password='123', admin=True))
db.session.commit()
The problems was the init_app, use the app_context, and I'm importing the wrong User module (tks Fian)

Error "NameError: name 'UsersAdmin' is not defined" when moved all classes to another file

Short story. I took this example:https://github.com/MrJoes/Flask-Admin/tree/master/examples/sqla i played with it and everything was fine until i decided what i want to split app.py(main file) to two parts. In main file app.py i will keep views and in another models.py i will keep all classes. Both files are in same folder.
Issue. I get error Error when running my app.py file:
"NameError: name 'UserAdmin' is not defined"
This is part from app.py file where i try to call Class UserAdmin from models.py file:
import os
import os.path as op
from flask import Flask, render_template, request, redirect, url_for, abort, session, flash
from flask_sqlalchemy import SQLAlchemy, Model
from flask_login import UserMixin, session, LoginManager, login_user, login_required, logout_user
from flask_bcrypt import Bcrypt,check_password_hash,generate_password_hash
from models import *
from flask_admin import Admin, BaseView, expose
app = Flask(__name__)
app.config['SECRET_KEY'] = '123456790'
app.config['DATABASE_FILE'] = 'db.sqlite'
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///' + app.config['DATABASE_FILE']
app.config['SQLALCHEMY_ECHO'] = True
db = SQLAlchemy(app)
bcrypt = Bcrypt(app)
admin = Admin(app, name='Admin Site', template_mode='bootstrap3')
# Add views. This is where it fails
admin.add_view(UserAdmin(User, db.session))
models.py file where is described UserAdmin part:
from wtforms import validators
from app import db, app, url_for, admin
from flask_admin.contrib import sqla
from flask_admin.contrib.sqla import filters, ModelView
from flask_login import UserMixin
...
# Create models
class User(db.Model):
id = db.Column(db.Integer, primary_key=True)
first_name = db.Column(db.String(100))
last_name = db.Column(db.String(100))
username = db.Column(db.String(80), unique=True)
email = db.Column(db.String(120), unique=True)
# Required for administrative interface. For python 3 please use __str__ instead.
def __str__(self):
return self.username
class UserInfo(db.Model):
id = db.Column(db.Integer, primary_key=True)
key = db.Column(db.String(64), nullable=False)
value = db.Column(db.String(64))
user_id = db.Column(db.Integer(), db.ForeignKey(User.id))
user = db.relationship(User, backref='info')
def __str__(self):
return '%s - %s' % (self.key, self.value)
class UserAdmin(sqla.ModelView):
inline_models = (UserInfo,)
...
If someone could point me what i am doing wrong there it would be very nice.
Thanks

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